Blade structure and axial flow fan

Abstract

The application relates to the technical field of axial flow fans and discloses a fan blade structure. The fan blade structure comprises a blade and an assembly structure. The root of the blade is provided with a first reinforcing structure. The first reinforcing structure is a hollow conical structure. The conical surface of the first reinforcing structure at least partially protrudes from the surface of the blade. The top of the first reinforcing structure is directed towards the top of the blade. The bottom of the first reinforcing structure is directed towards the root of the blade. The assembly structure is connected with the root of the blade. The assembly structure is coaxially arranged with the hollow conical structure. The assembly structure is used for mounting the fan blade structure on a hub disc. The root of the disclosed fan blade structure is provided with a hollow conical structure as a reinforcing structure. On one hand, the self-weight of the fan blade can be reduced, so that the material cost of the fan blade is reduced, and the load of a motor is reduced. On the other hand, the thickness design difference between the root of the blade and other parts can be reduced. When the fan blade is processed in the mode of injection molding, the shrinkage caused by the excessive thickness difference can be prevented. The application further discloses an axial flow fan.

Description

Technical Field

[0001] This application relates to the field of axial flow fan technology, for example to a fan blade structure and an axial flow fan. Background Technology

[0002] Currently, large air-cooled air conditioning outdoor units typically use large-diameter axial flow fans. Axial flow fan assemblies on the market come in two types of blades: one-piece injection molded and made of metal.

[0003] However, injection molding is generally not chosen for large-diameter axial flow fan blades because the injection molding equipment used in the production of large axial flow fans is large in tonnage, has high requirements, and has many limiting factors. In addition, the large air volume will inevitably cause a large load on the overall structure. Thickening the local weak areas will have negative effects, making the fan blades prone to uneven cooling and shrinkage during injection molding, resulting in shrinkage, internal air bubbles, and affecting structural strength. Furthermore, the molding time is too long, resulting in low production efficiency. Therefore, a disassembled structure is generally chosen, where the large axial flow fan blades are broken down into hubs and blades, processed separately, and then assembled.

[0004] The split structure comes in two forms: an all-metal combination of carbon steel hubs and aluminum alloy blades, or a metal-plastic combination of aluminum alloy hubs and PA6 plastic nylon blades.

[0005] The overall structure of all-metal wind turbine blades typically consists of a varying number of aluminum alloy blades connected to a carbon steel hub by rivets. A portion of the blade's back is attached to the hub and riveted together, forming a cantilever structure in the overlapping riveted area. For such large axial flow wind turbine blades, the outer side of the blade bears a very large moment of inertia. This cantilever structure easily leads to stress concentration near the contact area between the blade and the hub, as well as at the rivet holes. The alternating stress on the blade exacerbates material fatigue, causing fatigue failure and resulting in blade cracks. Furthermore, the metal blades cannot be improved by locally thickening weak areas. During operation, the flutter force generated by the wind turbine blades is transmitted to the area near the hub-blade contact area. Since the carbon steel hub is much stronger than the aluminum alloy blades, cracks first appear on the blades, then develop into more extensive fractures, and finally breakage.

[0006] Furthermore, since the riveted surfaces cannot be completely smooth and flat, and cannot achieve a perfect fit, gaps are inevitable. Therefore, during long-term operation, this cantilever structure continuously exerts pulling and tearing forces on the rivets and rivet holes, which will exacerbate the further expansion of the gaps. For such large-diameter wind turbines, the moment of inertia and the forces they are subjected to are very large, posing a huge safety hazard during long-term operation.

[0007] In addition, because the circumferential edge of the rivet hole cannot be guaranteed to be smooth and unaffected by tearing, micro-cracks are also prone to appear at the blade riveting joint. Under the influence of blade vibration, these cracks are prone to propagate and cause fatigue fracture risk.

[0008] Simply increasing the contact area between the hub and the blades will shift the location of blade breakage to the outer contour, but it will not fundamentally prevent blade breakage. In addition, it will lead to a surge in the weight of the wind turbine blades, increasing the motor load and significantly increasing the cost of wind turbine blade materials. Summary of the Invention

[0009] To provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended as a general commentary, nor is it intended to identify key / important components or describe the scope of protection of these embodiments, but rather as a prelude to the detailed description that follows.

[0010] This disclosure provides a blade structure and an axial flow fan to improve the strength of large-diameter axial flow blades.

[0011] In some embodiments, the wind turbine structure includes a blade and an assembly structure. A first reinforcing structure is provided at the root of the blade. The first reinforcing structure is a hollow conical structure. The conical surface of the first reinforcing structure protrudes at least partially from the surface of the blade. The apex of the first reinforcing structure faces the top of the blade, and the bottom of the first reinforcing structure faces the root of the blade. The assembly structure is connected to the root of the blade and is coaxially arranged with the hollow conical structure. The assembly structure is used to mount the wind turbine structure onto the hub disc.

[0012] In some embodiments, the assembly structure includes a mounting cylinder, which is a hollow structure with openings at both ends, and the mounting cylinder is connected to the first reinforcing structure.

[0013] In some embodiments, a second reinforcing structure is provided at the root of the blade.

[0014] In some embodiments, the second reinforcing structure includes a first reinforcing rib, which is disposed along the contact surface between the hollow conical structure and the blade.

[0015] In some embodiments, the second reinforcing structure further includes a second reinforcing rib, the first end of which is connected to the top of the hollow conical structure, and the second end of which is connected to the bottom of the hollow conical structure.

[0016] In some embodiments, the second reinforcing rib is a U-shaped structure protruding from the surface of the wind turbine blade structure.

[0017] In some embodiments, the middle portion of the second reinforcing rib is close to the leading edge of the blade.

[0018] In some embodiments, the cross-section of the second reinforcing rib is trapezoidal.

[0019] In some embodiments, the axial flow fan includes a hub disk and any of the blade structures described above; the edge of the hub disk is provided with a plurality of mounting grooves, which correspond to the assembly structure of the blade structure, and the mounting grooves are used to radially limit the blade structure on the hub disk.

[0020] In some embodiments, the wheel hub disc includes a first disc body and a second disc body. The edge of the first disc body is provided with a plurality of arc-shaped first limiting grooves, and the edge of the second disc body is provided with a plurality of arc-shaped second limiting grooves. The first disc body and the second disc body are symmetrically arranged, and the first limiting grooves and the second limiting grooves constitute an installation groove.

[0021] The fan blade structure and axial flow fan provided in this disclosure can achieve the following technical effects:

[0022] The disclosed wind turbine blade structure reduces the blade's weight and material cost by incorporating a hollow conical structure at the blade root. This weight reduction also lowers the motor load. Furthermore, while strengthening the structure, it also minimizes the thickness difference between the blade root and other parts, preventing excessive thickness in this area. When the wind turbine blade is manufactured using injection molding, this prevents significant thickness differences with other parts of the blade, thus avoiding shrinkage.

[0023] Furthermore, the cone surface protruding at least partially from the blade surface can enhance the strength of the blade root; with the cone apex of the hollow cone structure facing the top of the blade and the cone base of the first reinforcing structure facing the root of the blade, the stronger end of the first reinforcing structure can be close to the root of the blade to better improve the strength of the wind turbine structure.

[0024] The above general description and the description below are exemplary and illustrative only and are not intended to limit this application. Attached Figure Description

[0025] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations and drawings do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are shown as similar elements. The drawings are not to be scaled. And wherein:

[0026] Figure 1 This is a cross-sectional structural schematic diagram of an axial flow fan provided in an embodiment of this disclosure;

[0027] Figure 2 This is a schematic diagram of a wind turbine structure provided in an embodiment of this disclosure;

[0028] Figure 3 This is an exploded view of a wind turbine blade structure provided in an embodiment of this disclosure;

[0029] Figure 4This is a schematic diagram of the structure of a limiting plug provided in an embodiment of this disclosure;

[0030] Figure 5 This is a schematic diagram of another axial flow fan provided in an embodiment of this disclosure;

[0031] Figure 6 This is an exploded schematic diagram of an axial flow fan provided in an embodiment of this disclosure;

[0032] Figure 7 This is a schematic diagram of another axial flow fan provided in an embodiment of this disclosure;

[0033] Figure 8 This is a schematic diagram of the structure of a wheel hub disc provided in an embodiment of this disclosure;

[0034] Figure 9 This is an exploded view of a wheel hub disc provided in an embodiment of this disclosure.

[0035] Figure label:

[0036] 10: Wind turbine blade structure; 11: Blade; 111: Hollow conical structure; 112: First reinforcing rib; 113: Second reinforcing rib; 12: Assembly structure; 121: Mounting cylinder; 1211: First tooth; 1212: Annular reinforcing rib; 13: Limiting insert; 131: Second tooth; 132: First positioning structure;

[0037] 20: Wheel hub disc; 21: First disc body; 211: First limiting groove; 22: Second disc body; 221: Second limiting groove; 23: Second positioning structure;

[0038] 30: Motor shaft assembly parts. Detailed Implementation

[0039] To provide a more detailed understanding of the features and technical content of the embodiments of this disclosure, the implementation of the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The accompanying drawings are for illustrative purposes only and are not intended to limit the embodiments of this disclosure. In the following technical description, for ease of explanation, several details are used to provide a full understanding of the disclosed embodiments. However, one or more embodiments may still be implemented without these details. In other cases, well-known structures and devices may be simplified in their depiction to simplify the drawings.

[0040] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this disclosure described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0041] In this disclosure, the terms "upper," "lower," "inner," "middle," "outer," "front," and "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for better description of the embodiments of this disclosure and their implementations, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to require them to be constructed and operated in a specific orientation. Furthermore, some of the aforementioned terms may be used to indicate other meanings besides orientation or positional relationship; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in the embodiments of this disclosure according to the specific circumstances.

[0042] Furthermore, the terms "set up," "connect," and "fix" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure according to the specific circumstances.

[0043] Unless otherwise stated, the term "multiple" means two or more.

[0044] In this embodiment of the disclosure, the character " / " indicates that the objects before and after it are in an "or" relationship. For example, A / B means: A or B.

[0045] The term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0046] The root of blade 11 is the mounting end of blade 11, the tip of blade 11 is the end of blade 11 away from the mounting end, and the leading edge of blade 11 is the edge located on the side of the direction of rotation of blade 11. The trailing edge of blade 11 is the edge located on the side of the direction of rotation of blade 11.

[0047] It should be noted that, unless otherwise specified, the embodiments and features described in the present disclosure can be combined with each other.

[0048] Combination Figure 1-4 As shown, this embodiment of the present disclosure provides a wind turbine structure 10, including blades 11 and assembly structure 12.

[0049] The root of the blade 11 is provided with a first reinforcing structure, which is a hollow conical structure 111. The conical surface of the first reinforcing structure protrudes at least partially from the surface of the blade 11. The apex of the first reinforcing structure faces the top of the blade 11, and the bottom of the first reinforcing structure faces the root of the blade 11.

[0050] The assembly structure 12 is connected to the root of the blade 11. The assembly structure 12 is coaxially arranged with the hollow conical structure 111. The assembly structure 12 is used to install the wind turbine structure 10 on the hub disk 20.

[0051] It is understandable that the conical surface protruding at least partially from the surface of the blade 11 can enhance the strength of the root of the blade 11; with the cone apex of the hollow conical structure 111 facing the top of the blade 11 and the cone base of the first reinforcing structure facing the root of the blade 11, the end of the first reinforcing structure with higher strength can be close to the root of the blade 11 to better improve the strength of the wind turbine structure 10.

[0052] The wind turbine structure 10 provided in this embodiment reduces the weight of the wind turbine by providing a hollow conical structure 111 at the root of the blade 11, thereby reducing the material cost of the wind turbine and reducing the motor load. On the other hand, while strengthening the structure, it can also reduce the thickness design difference between the root of the blade 11 and other parts, avoiding excessive local thickness. When the wind turbine is processed by injection molding, this can prevent the thickness difference with other parts of the wind turbine from being too large, resulting in shrinkage.

[0053] Optionally, the assembly structure 12 includes a mounting cylinder 121, which is a hollow structure with openings at both ends, and the mounting cylinder 121 is connected to the first reinforcing structure.

[0054] Understandably, the hollow conical structure 111 is connected to the mounting cylinder 121, forming a cavity structure of a cone and cylinder combination. This further improves the overall strength of the blade 11. Furthermore, the fit between the cylindrical structures, compared to the fit between the sheet-like structures, improves the fit between the wind turbine blade 10 and the hub disc 20, reducing the presence of gaps.

[0055] As an example, combined Figure 1 , 3As shown in Figure 4, the first end of the mounting cylinder 121 is connected to the hollow conical structure 111, and the second end is used to install the limiting plug 13. The side of the limiting plug 13 away from the blade 11 has a first positioning structure 132, which is used to engage with the second positioning structure 23 of the hub disc 20. The inner wall of the second end of the mounting cylinder 121 has a first tooth 1211. A step is provided on the inner wall of the second end of the mounting cylinder 121, and the limiting plug 13 is installed on the step. The edge of the limiting plug 13 has a second tooth 131. The first tooth 1211 engages with the second tooth 131, and the installation angle of the blade 11 can be adjusted by adjusting the relative position of the limiting plug 13 and the mounting cylinder 121. The first positioning structure 132 can be a lever, and the second positioning structure 23 can be a positioning groove, corresponding to the lever and used to limit the lever. A scale can be provided on the surface of the limiting plug 13.

[0056] Preferably, the end of the mounting cylinder 121 is provided with an annular reinforcing rib 1212, the outer diameter of which is larger than the outer diameter of the mounting cylinder 121. A step is provided on the inner wall of the annular reinforcing rib 1212, and the limiting insert 13 is mounted on the step.

[0057] Optionally, a second reinforcing structure is provided at the root of the blade 11. This can enhance the strength of the root of the blade 11.

[0058] Combination Figure 2 As shown, optionally, the second reinforcing structure includes a first reinforcing rib 112, which is disposed along the contact surface between the hollow conical structure 111 and the blade 11. This enhances the connection strength between the blade 11 and the hollow conical structure 111.

[0059] Optionally, the second reinforcing structure further includes a second reinforcing rib 113, the first end of which is connected to the cone apex of the hollow cone structure 111, and the second end of which is connected to the cone bottom of the hollow cone structure 111.

[0060] Understandably, the root of blade 11 is a weak point, and structural strength can be reinforced in the areas of this injection-molded blade 11 that require reinforcement. The root of blade 11 experiences the greatest stress, and the strength of the root of blade 11 can be enhanced by setting a second reinforcing rib 113.

[0061] Optionally, the second reinforcing rib 113 is a U-shaped structure protruding from the surface of the blade structure 10.

[0062] It is understandable that the root of blade 11 is subjected to the greatest force, and the protruding structure of the second reinforcing rib 113 can further strengthen the strength of the root of blade 11.

[0063] Optionally, the middle part of the second reinforcing rib 113 is close to the leading edge of the blade 11.

[0064] Understandably, the second reinforcing rib 113 has a semi-enclosed U-shaped protrusion structure, which can strengthen the weak area at the root of the blade 11.

[0065] Optionally, the cross-section of the second reinforcing rib 113 is trapezoidal. This can improve the strength of the second reinforcing rib 113.

[0066] As an example, blade 11 has a flanged structure at the top, a reinforcing structure at the root, a toothed structure at the leading edge, and a grooved structure at the trailing edge. The grooved structure is located near the top of blade 11, and the height ratio of the grooved structure to the height of the blade structure 10 is 4:5. The depth of the grooved structure is 20mm-30mm. It can be understood that the toothed structure at the leading edge of blade 11 forms a biomimetic "comb-like" structure similar to a bird's wing, while the concave structure at the trailing edge places the lowest point of the concave edge at approximately 0.8 of the blade diameter, with a depth of about 25mm. The concave structure at the trailing edge improves the stress distribution on the blade 11 surface, causing the high-pressure airflow on the pressure side of blade 11 to flow towards the suction side earlier, resulting in a localized pressure increase. This confines the boundary layer separation caused by the increased pressure to the concave area, thereby reducing noise by approximately 1dB(A) at the same airflow volume, reducing blade weight, and lowering fan power consumption. The top is designed with a flanged structure, which helps to reduce turbulence pulsation and further reduce the noise of the fan blades.

[0067] Combination Figure 5-9 As shown, this embodiment of the present disclosure provides an axial flow fan, including a hub disk 20 and a fan blade structure 10 as described above. The edge of the hub disk 20 is provided with a plurality of mounting grooves, which correspond to the assembly structure 12 of the fan blade structure 10. The mounting grooves are used to radially limit the fan blade structure 10 on the hub disk 20.

[0068] Understandably, the fan blades are installed and fixed in the mounting slot of the hub disc 20 via the assembly structure 12.

[0069] As an example, the main body of the wheel hub includes a wheel hub disc 20 and a motor shaft assembly 30. Both the wheel hub disc 20 and the central portion of the motor shaft assembly 30 have holes in their middle sections. The motor shaft assembly 30 passes through and is installed within these holes. The motor shaft assembly 30 can be replaced according to the specifications and dimensions of the motor shaft.

[0070] As another example, the outer part of the mating area between the fan blade and the hub disc 20 is a smooth cylindrical structure with a raised rib on the top, which serves as a limit in the flange hub and also as a structural reinforcement.

[0071] Combination Figure 6-9 As shown, optionally, the wheel hub disc 20 includes a first disc body 21 and a second disc body 22. The edge of the first disc body 21 is provided with a plurality of arc-shaped first limiting grooves 211. The second disc body 22 is symmetrically arranged with the first disc body 21 and is detachably connected. The edge of the second disc body 22 is provided with a plurality of arc-shaped second limiting grooves 221. The first limiting grooves 211 and the second limiting grooves 221 constitute an installation groove.

[0072] Understandably, considering versatility and cost optimization, the first disc 21 and the second disc 22 can be made into a completely symmetrical structure, and a groove structure is set inside for the installation limit of the fan blade. The fan blade is installed between the first disc 21 and the second disc 22, and finally assembled and locked with fastening screws.

[0073] The following is combined Figures 1 to 9 The axial flow fan of this disclosure will be described as shown.

[0074] To address the fracture problem of the all-metal blades 11, the axial flow fan disclosed herein adopts a combination solution of a metal hub and plastic blades.

[0075] The wheel hub, similar to a flange structure, is first machined into a rough blank using aluminum alloy die casting, followed by fine machining and other detail treatments. Its main body includes a wheel hub disc 20 and a motor shaft assembly 30. Both the wheel hub disc 20 and the central motor shaft assembly 30 have holes in their center. The motor shaft assembly 30 passes through and is installed within these holes. The motor shaft assembly 30 can be replaced according to the specifications and dimensions of the motor shaft.

[0076] The hub disc 20 includes a first disc body 21 and a second disc body 22. Considering versatility and cost optimization, the first disc body 21 and the second disc body 22 can be made into a completely symmetrical structure, and a groove structure is set inside for the installation limit of the fan blade. The fan blade is installed between the first disc body 21 and the second disc body 22, and finally assembled and locked with fastening screws.

[0077] The fan blades are injection molded from PA6 plastic nylon material, avoiding the possibility of internal micro-cracks in metal materials during cold stamping, thus eliminating the possibility of metal fan blade breakage at the source. Furthermore, local structural reinforcement can be carried out on areas of the fan blade that are subjected to high stress and have relatively weak strength (e.g., by thickening and / or setting reinforcing ribs).

[0078] The hub disc 20 is provided with a corresponding number of mounting slots according to the number of fan blades. The edge of the first disc body 21 is provided with a number of first limiting slots 211, and the edge of the second disc body 22 is provided with a number of second limiting slots 221. The first limiting slots 211 and the second limiting slots 221 are matched to form mounting slots.

[0079] The first limiting groove 211 and the second limiting groove 221 have the same structure, both including a blade assembly groove and a positioning groove. The blade assembly groove is a groove located on the outer edge of the first disc 21, and the positioning groove is located at the bottom of the blade assembly groove. The blade assembly groove is used to limit the movement of the blade 11 in the direction of its center, and the positioning groove is used to adjust the installation angle of the blade.

[0080] The fan blade has a groove on the mounting side for installing the limiting plug 13. Inside the groove is a key tooth structure corresponding to the limiting plug 13. The evenly spaced angle and number of key tooth structures are set according to actual needs.

[0081] By incorporating reinforcing ribs into the weakest areas of the blade 11, structural strength can be enhanced in these locally reinforced areas of the injection-molded blade 11. The root of the blade 11 experiences the greatest stress, and a reinforcing rib structure with a semi-enclosed U-shaped protrusion is placed on its back at this location. The cross-section of the reinforcing rib is trapezoidal.

[0082] The mounting area where the blade 11 mates with the hub disc 20 is also the main stress-bearing part of the blade 11, and local reinforcement is also made here.

[0083] The outer surface of the mating area between the blade 11 and the hub is a smooth cylindrical structure with a raised rib at the top. This rib serves as a limit and structural reinforcement within the flange hub, and is thickened in this area. The internal cavity forms a combination of a cone and a cylinder. Firstly, this reduces the weight of the blade, thereby lowering material costs and reducing motor load. Secondly, it reduces the thickness difference between the root of the blade 11 and other parts, preventing excessive thickness in this area. When the blade is manufactured using injection molding, this prevents significant thickness differences and shrinkage. Thirdly, it maximizes the overall strength of the blade 11. This structure protrudes from the surface of the blade 11 and integrates with the aforementioned reinforcing rib structure, further enhancing the structural strength of the blade 11.

[0084] The inner side of the mounting cylinder 121 has a first tooth 1211 along its circumference, and the limiting plug 13 has a second tooth 131 along its outer circumference. The two fit together. The thin strip on the back of the limiting plug 13 is aligned with the axial direction of the motor and matches the positioning groove structure in the hub disc 20. The installation direction of the limiting plug 13 is aligned with the axial direction of the motor shaft and is inserted longitudinally into the flange hub. After the limiting plug 13 is fully assembled and positioned, the installation angle of the blade 11 can be adjusted by adjusting the relative position of the limiting plug 13 and the mounting cylinder 121. For example, if the number of teeth in the limiting plug 13 is N, rotating one tooth position adjusts the angle by 360° / N. Thus, by adjusting the installation angle of the fan blade, the installation requirements of blades 11 with different performance characteristics can be met.

[0085] The blade's leading edge features a unique, bird-wing-like "comb-shaped" biomimetic structure, while the trailing edge has a concave structure. The lowest point of the concave trailing edge is located at approximately 0.8 mm in the diameter direction of the blade, with a depth of about 25 mm. The outer edge is designed with a flanged structure to further reduce the noise of the blade's operation.

[0086] The recessed structure at the impeller trailing edge improves the stress on the blade 11 surface, causing the high-pressure airflow on the pressure side of the blade 11 to flow towards the suction side in advance, resulting in a local pressure increase. This limits the boundary layer separation caused by the pressure increase to the recessed area, thereby reducing noise. At the same air volume, the noise can be reduced by about 1 dB(A), and the weight of the blades and the power consumption of the fan are also reduced.

[0087] Flanging the outer edge of the fan helps reduce turbulence and noise.

[0088] The foregoing description and accompanying drawings fully illustrate embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Parts and features of some embodiments may be included or substituted for parts and features of other embodiments. Embodiments of the present disclosure are not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from its scope. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A wind turbine blade structure, characterized in that, include: The blade (11) has a first reinforcing structure at its root. The first reinforcing structure is a hollow conical structure (111). The conical surface of the first reinforcing structure protrudes at least partially from the surface of the blade (11). The apex of the first reinforcing structure faces the top of the blade (11), and the bottom of the first reinforcing structure faces the root of the blade (11). The root of the blade (11) has a second reinforcing structure. The second reinforcing structure includes a second reinforcing rib (113). The second reinforcing rib (113) is a U-shaped structure protruding from the surface of the blade structure. The first end of the second reinforcing rib (113) is connected to the apex of the hollow conical structure (111), and the second end of the second reinforcing rib (113) is connected to the bottom of the hollow conical structure (111). The assembly structure (12) is connected to the root of the blade (11). The assembly structure (12) is coaxially arranged with the hollow conical structure (111). The assembly structure (12) is used to install the wind turbine structure (10) on the hub disc (20).

2. The wind turbine blade structure (10) according to claim 1, characterized in that, The assembly structure (12) includes: The mounting cylinder (121) is a hollow structure with openings at both ends, and the mounting cylinder (121) is connected to the first reinforcing structure.

3. The wind turbine blade structure according to claim 1, characterized in that, The second reinforcing structure also includes: The first reinforcing rib (112) is provided along the contact surface between the hollow conical structure (111) and the blade (11).

4. The wind turbine blade structure according to claim 1, characterized in that, The middle part of the second reinforcing rib (113) is close to the leading edge of the blade (11).

5. The wind turbine blade structure according to claim 1, characterized in that, The cross-section of the second reinforcing rib (113) is trapezoidal.

6. An axial flow fan, characterized in that, include: The wind turbine structure as described in any one of claims 1 to 5; The hub disc (20) has several mounting slots on its side, which correspond to the assembly structure (12) of the fan blade structure (10). The mounting slots are used to radially limit the fan blade structure (10) on the hub disc (20).

7. The axial flow fan according to claim 6, characterized in that, The wheel hub disc (20) includes: The first disc body (21) has several arc-shaped first limiting grooves (211) on its edge; The second disc (22) is symmetrically arranged with the first disc (21) and detachably connected. The edge of the second disc (22) is provided with a plurality of arc-shaped second limiting grooves (221). The first limiting groove (211) and the second limiting groove (221) constitute the mounting groove.

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